Fillmore County, NE: EPA's radon zone, explained

Fillmore County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. Rank it against the rest of the country and Fillmore County lands in the 71st percentile for radon potential.

Where Fillmore County sits nationally

Fillmore County, Nebraska is home to about 5,512 people across 575.37 square miles. Averaged across its land area, Fillmore County runs about 10 people per square mile. By population, Fillmore County is the 907th largest of every county sharing its EPA zone — the 15th percentile by population within that zone. EPA's geology-based Region 7 groups Fillmore County with 411 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Fillmore County

Fixing a home becomes an EPA recommendation past 4 pCi/L, and that is precisely the side of the line Fillmore County's Zone 1 prediction lands on, well above the roughly 1.3 pCi/L most US homes average. A Zone 1 rating means testing is worth doing sooner rather than later, but it is still county-wide average, not a reading for any single house — some homes in Fillmore County will test well under the action level, and EPA's guidance is to test regardless of zone.

Next steps for a home in Fillmore County

For a Fillmore County homeowner, the order is simple: test first, since a kit costs a small fraction of what mitigation would. Only if the result clears 4 pCi/L does a system — typically $800–$2,500, about $1,200 for a common install — become worth pricing out.

Find Nebraska's state radon program

For Fillmore County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Fillmore County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. Use code RADONZONE-10OFF at checkout for 10% off.

Where Fillmore County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Fillmore County's numbers. Whatever zone Fillmore County carries, the zone explainer covers what it does and doesn't tell you about any one house.